Many people use mobile devices, such as cell phones and personal digital assistants, to wirelessly communicate with wireless-communication networks. Mobile devices typically conduct these wireless communications by way of one or more radio access networks (RANs).
In a typical RAN, an area is divided geographically into a number of wireless coverage areas, such as cells and sectors, each defined by a radio frequency (RF) radiation pattern from a respective serving base transceiver station (BTS). Within each wireless coverage area, the serving BTS may provide one or more wireless links over which mobile devices may communicate with the RAN. In turn, the RAN may provide mobile devices with connectivity to the public switched telephone network (PSTN), one or more packet-data networks such as the Internet, and/or other transport networks. Thus, a mobile device may engage in various communication sessions via the RAN including, for example, voice communication sessions and/or packet-data communication sessions. A particular communication session that a mobile device engages in may be referred to as a “call,” whether the communication session is a voice communication session, a packet-data communication session, or another type of communication session.
A mobile device may initiate a call within a first wireless coverage area by, for example, placing or receiving the call in the first wireless coverage area. If the mobile device then leaves the first wireless coverage area and enters a second wireless coverage area, the call may be handed off to the second wireless coverage area. In this way, the mobile device may continue the call when moving from the first wireless coverage area to the second wireless coverage area. Thus, a given call that is being carried out within a particular wireless coverage area may have been a new call origination within the wireless coverage area, or may have been a handoff into the wireless coverage area.
A BTS will have a limited amount of resources available for handling calls within its wireless coverage area. Such resources may include, for example, forward-link transmission power, Walsh codes that uniquely define communication channels, and/or other channel elements such as hardware and/or software components that are configured to perform encoding, modulation, and/or other operations to facilitate the transmission of data. Other examples of the resources that are required for handling calls may exist as well, and the particular resources employed by a given BTS may vary depending on the particular communication protocol used by the BTS. Generally, the resources available for handling calls within a wireless coverage area of a BTS may be referred to as the capacity of the wireless coverage area. Thus, a given wireless coverage area will have a limited total capacity available for handling calls.
Each new call origination and each handoff into a wireless coverage area will require a certain amount of the total capacity of the wireless coverage area. Accordingly, a first portion of the total capacity may be set aside to support new call originations, and a second portion of the total capacity may be set aside to support handoffs. In other words, the RAN may impose a limit on extent of the capacity allocated to new call originations in the wireless coverage area, and the RAN may also impose a limit on extent of capacity allocated to handoffs into the wireless coverage area.
When the limit on extent of capacity allocated to new call originations in the wireless coverage area has been met or exceeded, a mobile device that requests a new call origination within the wireless coverage area may be denied service in the wireless coverage area. Similarly, when the limit on extent of capacity allocated to handoffs into the wireless coverage area has been met or exceeded, a mobile device that requests handoff into the wireless coverage area may be denied service in the wireless coverage area.
Such denials of service may negatively impact the quality of a mobile device user's experience with a given RAN. Therefore, it is generally desirable to control allocations of network capacity so as to help minimize the occurrence of denials of service.